Suffering an injury is often painful and upsetting to the injured party. The body typically responds in several fashions, often dependent upon the type and severity of the injury. One such response is the production of scar tissue, whose growth may impede other parts of the body. The scar tissue's growth can lead to other problems within the body. For example, scar tissue can form around and/or affect a lumen of the body, thereby potentially narrowing the lumen. This narrowing of the lumen, also called a stricture, typically reduces the amount of fluid that can flow through the lumen.
An example of a lumen that a stricture can affect is the urethra. The male urethra is generally a tubular passageway extending from the bladder to the end of the penis. As urine travels from the bladder and out of the body, the urine passes through the urethra. A stricture, however, narrows the urethra. This narrowing of the urethra (i.e., lumen) can impede fluid flow (e.g., urine) through the urethra, cause pain during use of the urethra, and/or require medical intervention to expand or stretch the obstruction.
A trauma to the urethra or surrounding areas is an example of an event that can cause the formation of a stricture. A trauma can be the result of an external injury, such as a straddle injury (e.g., falling onto a bicycle frame). Pelvic fractures, which can occur as a result of an automobile accident, can also lead to strictures of the urethra. Surgical procedures involving the urethra can cause stricture formation. Other causes of a urethral stricture include an infection, such as gonorrhea, or inflammation of an area of the urethra.
To treat a stricture, medical professionals (e.g., doctors, nurses, hospital employees, or people with medical training) often have several options. One option is a procedure called dilation. Dilation is performed in the medical professional's office and involves stretching of the stricture using progressively larger dilators. Another option, which medical professionals perform in the operating room using an endoscopic instrument, is called internal urethrotomy. Internal urethrotomy involves an internal incision of the stricture through the penis to open the stricture. Thus, the medical professional typically cuts the stricture to remove the narrowing of the urethra.
After the surgical incision through the stricture, the stricture's wound edges heal. If left unattended, the stricture's wound edges can heal together, likely resulting in a larger stricture than present before the surgical incision. Thus, the surgery's objective of removing the narrowing of the urethra may be met temporarily, but the healing of the stricture can narrow the urethra even further.
The medical professional typically places a catheter into the urethra after the surgical incision is made. The catheter typically keeps the urethra opened after the surgery until the catheter is removed (after a certain period of time). In addition to helping prevent subsequent recurrence of a stricture, patency of the urethra is important for several reasons, such as to aid in the healing of the urethra, for the drainage of urine, and to enable vascular flow through the urethra. One such type of catheter that a medical professional inserts is a Foley catheter.
The technique of using a catheter to maintain urethral patency, however, is subject to several drawbacks. First, the catheter that the medical professionals insert to maintain the proper opening of the urethra has a fixed diameter. Thus, because catheters are typically limited to a fixed diameter, wound edges can form up to the diameter of the catheter. Moreover, dilation devices, such as balloons, can hinder or prevent blood or other bodily fluids from flowing through the urethra because the passageway or a large portion of the passageway is typically blocked by the dilation device. Catheters may also suffer from this drawback, as their diameter can limit the amount of fluid that can flow in and out of the urethra when attempting to prevent wound edges from approximating.
Although described above with a urethra, a stricture may form around any other type of lumen, such as a person's esophagus. Further, the problems described above also apply to these other types of lumens. Thus, there is a need to reduce the approximation of wound edges of a stricture while not preventing fluid flow through the lumen.